(CNN) -- Inter Milan came from behind to win for the second time in a week to keep their Italian title hopes alive with a 3-1 victory over relegation-threatened Atalanta on Saturday.

Jose Mourinho's team followed up the stunning midweek victory over European champions Barcelona to move two points clear of second-placed Roma, who host Sampdoria on Sunday.

But key Dutch midfielder Wesley Sneijder is in doubt for the second leg of the Champions League semifinal in Spain on Wednesday after coming off at halftime with a thigh injury.

Atalanta, third from bottom with three matches to play, took a shock fifth-minute lead through Simone Tiribocchi but Inter hit back with three unanswered goals as they did against Barca.

Argentina striker Diego Milito scored his 20th Serie A goal of the season to level with a lob in the 24th minute, then Kenyan midfielder McDonald Mariga scored his first for the defending champions with a shot that deflected in off teammate Sulley Muntari.

Cristian Chivu, playing at left-back in a revamped defense due to absent Brazilian right-back Maicon's dental problems, sealed victory with 13 minutes to play with a super long-range shot to extend the Nerazzurri's unbeaten home run to 40 league games.

The Romanian was delighted after scoring his first goal for Inter following his move from Roma in 2007.

"We're pleased with the victory. It wasn't easy because we were behind, but we knew how to react," he told the club's Web site.

"It was an important goal for me and the team: for me because it hasn't been an easy period for me, and for the team because we have to keep winning until the end. Roma's game tomorrow? I won't watch it. The last time I watched Roma, they won.

"From tomorrow we will start thinking about Barcelona. It's a historic moment for us. We have to give our all."

Third-placed AC Milan crashed to a 3-1 defeat at European hopefuls Palermo in Saturday's late match, and now trail their city rivals by nine points with three matches to play.

Palermo moved above Sampdoria into fourth spot after going 2-0 up in the first 18 minutes with goals from defender Cesare Bovo and Uruguayan striker Abel Hernandez.

Dutch midfielder Clarence Seedorf pulled one back for the visitors 10 minutes after halftime, but striker Fabrizio Miccoli restored the Sicilians' two-goal cushion on 66.